<p>
  In the last chapter we learned the definition of mean and variance, which are kind of <strong>point estimation</strong>. Point estimation means using sample data to calculate a single value which is to serve as a 'best estimation' of an unknown population. However, this it not enough because point estimations can be deceiving. We need to use more rigorous methods to test our ideas. That's why we consider distribution and hypothesis testing. Random variable distribution is the basis for almost all quantitative finance topics: linear regression, CAPM, Black-Scholes, binomial tree pricing, etc.
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